about the rPref package and Gradient color legend

[lily li]

Hi ggplot users,

I have a question about the package, so see if anyone can help me. In the function, we use different colors for different levels. Is it possible to show the legend of different colors in a gradient rather than point legend? This way, it can save space.

I think this may be similar to the legend in ggplot, so how to show legend of color points as a gradient bar? Thanks for your help.